The Importance of Roses in Religion

The structured prayer form of 150 Hail Marys was termed a "rosary". This expression came from the Latin rosarium or rosarius, a name given to works collecting the best of teachings. Arnold of Villanova wrote a Rosarius Philosophorum, explaining that it was a compendium, a thesaurus, a treasury of philosophy. Here the symbolism of the rosary stands as a precious anthology of spirituality.
Our Lady of the Rosary is Our Lady of the roses, because the flowers are the symbols of greeting offered to the Mother of God. We greet her with spiritual flowers.

Rosa Mystica ~ Mystical Rose

The rose was symbol of mystery (antiquity), and for early Christians a metaphor of both martyrdom and paradise. A classical illustration of Mary shows her emerging from a giant rose bush planted in a French garden. Two potted rose trees flank the central image. All three serve as visual support to the scriptural references of the rose symbolism applied to Mary. The rose bush with open petals serving as throne of Our Lady bears the following caption: “Open up your petals like roses planted near running water”

Rosicrucian Rose

The rose is a yonic symbol associated with generation, fecundity, and purity. The fact that flowers blossom by unfolding has caused them to be chosen as symbolic of spiritual unfoldment. The red colour of the rose refers to the blood of Christ, and the golden heart concealed within the midst of the flower corresponds to the spiritual gold concealed within the human nature. The number of its petals being ten is also a subtle reminder of the perfect Pythagorean number. The rose symbolizes the heart, and the heart has always been accepted by Christians as emblematic of the virtues of love and compassion, as well as of the nature of Christ—the personification of these virtues.
Occasionally the symbol of a cross rising from a rose was used in connection with their activities.
The Rosicrucian rose was drawn upon the Round Table of King Arthur, and is the central motif for the links forming the chain from which the "Great George" is suspended among the jewels of The Order of the Garter.